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    <title>Document</title>
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    // // nudefined
    // var x;
    // alert(x)
    // 字符
    var str1 ="heoll word"
    var str2 ='heoll word'
    console.log(str1)
    console.log(str2)
    // var str3 ="heoll word"
    var str4 ='小明说；"小红很漂亮"'
    var str ="java"
    // JS中线运算等号右边语句
    str = str + "script";//字符串中+号是连接的意思 JavaScript
    console.log(str)
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